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1.
J Am Acad Dermatol ; 84(5): 1278-1284, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33010323

RESUMO

BACKGROUND: No long-term maintenance therapy has been tested in patients with seborrheic dermatitis (SD). OBJECTIVE: We sought to compare the efficacy and tolerance of tacrolimus 0.1% ointment versus ciclopiroxolamine 1% cream as maintenance therapy for severe SD. METHODS: This double-blind randomized controlled study was conducted from 2014 to 2017 in 5 Dermatology Departments and 15 dermatology practices in France. Consecutive patients with severe and chronic facial SD were included. Patients were initially treated with desonide 0.05% cream twice daily for 7 days. Patients cleared after this open phase were randomized to receive tacrolimus 0.1% or ciclopiroxolamine 1% cream 2 times a week 24 weeks. The primary endpoint was disease-free-duration, defined as the time from randomization to first relapse. RESULTS: One hundred fourteen patients were randomized (tacrolimus, n = 57; ciclopiroxolamine, n = 57). Twelve patients relapsed in the tacrolimus group after a median delay of 91.5 days (range 15-195 days) versus 23 patients in the ciclopiroxolamine group (median delay, 27 days [range 13-201 days]). Comparison of disease-free duration curves showed that patients in the tacrolimus group had a longer duration of complete remission than those in the ciclopiroxolamine group (P = .018), corresponding to a hazard ratio of relapse of 0.44 (95% confidence interval 0.22-0.89; P = .022). LIMITATIONS: The theoretical sample size was not reached. CONCLUSION: Tacrolimus 0.1% is more effective than ciclopiroxolamine 1% as maintenance therapy for patients with facial SD.


Assuntos
Ciclopirox/administração & dosagem , Dermatite Seborreica/tratamento farmacológico , Dermatoses Faciais/tratamento farmacológico , Quimioterapia de Manutenção/métodos , Tacrolimo/administração & dosagem , Adulto , Dermatite Seborreica/diagnóstico , Método Duplo-Cego , Esquema de Medicação , Dermatoses Faciais/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Resultado do Tratamento
3.
Mol Cancer Ther ; 6(10): 2747-56, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17938268

RESUMO

The bacterial cytosine deaminase (CD) gene, associated with the 5-fluorocytosine (5FC) prodrug, is one of the most widely used suicide systems in gene therapy. Introduction of the CD gene within a tumor induces, after 5FC treatment of the animal, a local production of 5-fluorouracil resulting in intratumor chemotherapy. Destruction of the gene-modified tumor is then followed by the triggering of an antitumor immune reaction resulting in the regression of distant wild-type metastasis. The global effects of 5FC on colorectal adenocarcinoma cells expressing the CD gene were analyzed using the proteomic method. Application of 5FC induced apoptosis and 19 proteins showed a significant change in 5FC-treated cells compared with control cells. The up-regulated and down-regulated proteins include cytoskeletal proteins, chaperones, and proteins involved in protein synthesis, the antioxidative network, and detoxification. Most of these proteins are involved in resistance to anticancer drugs and resistance to apoptosis. In addition, we show that the heat shock protein Hsp90beta is phosphorylated on serine 254 upon 5FC treatment. Our results suggest that activation of Hsp90beta by phosphorylation might contribute to tumor regression and tumor immunogenicity. Our findings bring new insights into the mechanism of the anticancer effects induced by CD/5FC treatment.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Citosina Desaminase/genética , Flucitosina/uso terapêutico , Genes Transgênicos Suicidas , Proteínas de Choque Térmico HSP90/metabolismo , Proteoma/metabolismo , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Sequência de Aminoácidos , Animais , Anexina A5/metabolismo , Biomarcadores Tumorais/metabolismo , Western Blotting , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Eletroforese em Gel Bidimensional , Técnicas de Transferência de Genes , Terapia Genética , Vetores Genéticos , Dados de Sequência Molecular , Fosforilação , Ratos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Transdução Genética , Células Tumorais Cultivadas/efeitos dos fármacos
4.
HPB (Oxford) ; 9(2): 112-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18333125

RESUMO

BACKGROUND: Pentoxifylline (PTX) has been shown to reduce hepatic injury after normothermic ischemia and reperfusion (I-R) in rat liver. AIM: The aim of this study was to evaluate the effects of PTX on liver expression of tumor necrosis factor alpha (TNFalpha) mRNA following normothermic liver I-R. MATERIALS AND METHODS: A segmental normothermic ischemia of the liver was induced in male Lewis rats by occluding the blood vessels including the bile duct to the median and left lateral lobes for 90 min. At the end of ischemia the nonischemic liver lobes were resected. Rats were divided into three groups: group 1, control Ringer lactate administration; group 2, PTX treatment; group 3, sham-operated control rats. PTX (50 mg/kg) was injected intravenously 30 min before and 60 min after induction of ischemia. Survival rates were compared and the serum activities of TNFalpha, serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) were measured. Histology of the liver was assessed 6 h after reperfusion. Liver TNFalpha mRNA was assessed by PCR amplification at 0, 60, 120, and 210 min after reperfusion. RESULTS: PTX treatment significantly increased 7 day survival (93.3%) compared with nontreated control rats (46.6%, p<0.007). The extent of liver necrosis and the release of liver enzymes were significantly decreased after PTX treatment. Serum activities of TNFalpha were significantly decreased and liver expression of TNFalpha mRNA was inhibited after PTX treatment. CONCLUSION: PTX protects the liver from ischemic injury and inhibits liver expression of TNFalpha mRNA.

5.
Mol Cell Proteomics ; 5(11): 2031-43, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16837577

RESUMO

To better understand the effects of antiandrogens on the prostate, we investigated the changes in the proteome of rat ventral prostate (VP) following treatment with a well characterized 5alpha-reductase inhibitor, finasteride. Sprague-Dawley rats were treated daily by gavage with finasteride at 0, 1, 5, 25, and 125 mg/kg/day. Changes in plasma hormone levels as well as the weight and histology of sex accessory tissues were determined after 28 days of treatment and showed a dose-related decrease of VP weights together with a marked atrophy of the tissue visible at the macroscopic and microscopic levels. In addition, significant reductions in seminal vesicle and epididymis weights were noted. VP proteins were analyzed by two-dimensional gel electrophoresis: 37 proteins, mainly involved in protein synthesis, processing, and cellular trafficking and in metabolism, detoxification, and oxidative stress, were identified as modulated by finasteride. The prominent feature of this study is the demonstration of finasteride dose-dependent up-regulation of a protein similar to l-amino-acid oxidase 1 (Lao1). An up-regulation of this protein was also observed with the antiandrogen flutamide. Lao1 expression occurred as early as 48 h after antiandrogen administration and persisted throughout the treatment duration. Immunohistochemistry showed that this protein was only detectable in epithelial cells and secretory vesicles. Altogether these data point to a potential use of Lao1 to reveal antiandrogen-induced prostate injury.


Assuntos
Inibidores Enzimáticos/administração & dosagem , Finasterida/administração & dosagem , Próstata/efeitos dos fármacos , Análise Serial de Proteínas , Proteínas/análise , Inibidores de 5-alfa Redutase , Animais , Eletroforese em Gel Bidimensional , Células Epiteliais/enzimologia , L-Aminoácido Oxidase/análise , L-Aminoácido Oxidase/metabolismo , Masculino , Tamanho do Órgão/efeitos dos fármacos , Fosforilação , Próstata/citologia , Próstata/metabolismo , Ratos , Ratos Sprague-Dawley , Vesículas Secretórias/enzimologia , Tirosina/metabolismo
6.
Int J Mol Med ; 14(2): 323-5, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15254786

RESUMO

The bacterial cytosine deaminase (CD) gene, associated to the 5-fluorocytosine (5-FC) prodrug, is one of the more widely used suicide systems in gene therapy. Introduction of the CD gene within a tumor induces, after 5-FC treatment of the animal, a local production of 5-fluorouracil (5-FU) resulting in intratumor chemotherapy. Destruction of the gene-modified tumor is then followed by the triggering of an anti-tumor immune reaction resulting in the regression of distant wild-type metastasis. In pre-clinical studies, 5-FC is generally administered by daily intraperitoneal injections. However, when used as an anti-fungal in humans, either IV or oral administration is used. In this study, we compared oral and intraperitoneal 5-FC administration in rats bearing a wild-type and a cytosine deaminase-expressing liver tumors. The results indicate that per os 5-FC administration is as efficient as intraperitoneal for the induction of CD-expressing tumor regression and the triggering of a distant bystander effect, acting on wild-type liver tumor and extra-hepatic metastasis.


Assuntos
Vacinas Anticâncer/administração & dosagem , Citosina Desaminase/biossíntese , Flucitosina/administração & dosagem , Terapia Genética/métodos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Administração Oral , Animais , Antimetabólitos/administração & dosagem , Linhagem Celular Tumoral , Citosina Desaminase/genética , Infusões Parenterais , Neoplasias Pulmonares/secundário , Metástase Neoplásica , Transplante de Neoplasias , Ratos
7.
J Feline Med Surg ; 6(2): 111-8, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15123156

RESUMO

Feline infectious peritonitis virus (FIPV) is a coronavirus that induces a fatal systemic disease mediated by an inappropriate immune response. Most previous vaccination attempts against FIPV were unsuccessful because IgG antibodies against the surface protein enhance the infection. However, two studies have shown that poxvirus vectors (vaccinia WR and canarypox) expressing only the FIPV membrane (M) protein can elicit a partially protective immunity which is supposed to be cell-mediated (Virology 181 (1991) 327; International patent WO 97/20054 (1997)). In our study, we report the construction of another poxvirus, the modified vaccinia virus Ankara (MVA), as an expression vector for the FIPV M protein. In this vector, the M gene has been inserted downstream a strong early/late promoter, whereas the two previously described poxviruses expressed the M protein during their early stage only. The immunogenicity of the recombinant MVA-M was evaluated in the murine model which revealed an effect of the vector on the Th1/Th2 balance. The vaccine was then tested in cats to evaluate its efficacy in an FIPV 79-1146 challenge. Vaccinated kittens developed FIPV-specific antibodies after immunization, however, none of them was protected against FIPV. Our results suggest a crucial role for the type of poxviral promoter that must be used to induce an effective immune response against FIPV.


Assuntos
Coronavirus Felino/genética , Peritonite Infecciosa Felina/prevenção & controle , Vaccinia virus/imunologia , Vacinas Virais , Animais , Gatos , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Organismos Livres de Patógenos Específicos , Resultado do Tratamento , Vacinação/veterinária
8.
J Leukoc Biol ; 75(4): 680-8, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-14704364

RESUMO

Hox genes, which are key regulators of cell fate and pattern formation during embryogenesis, are also important regulators of hematopoiesis, and different combinations of Hox gene products are involved in lineage commitment or maturation. However, their molecular and cellular modes of action are not yet completely understood. Recent studies have indicated that Hox genes are involved in the regulation of cell-extracellular matrix (ECM) interactions and cell migration. Here, we report that Hox A7, a gene frequently overexpressed in acute myeloid leukemia, is down-regulated during HL-60 monocytic differentiation. Using a model in which HL-60 cells are induced to differentiate toward the monocytic lineage with bone marrow stromal-like cells, we demonstrate that Hox A7-sustained expression disturbs the regulation of cell adhesive and migratory capacities on fibronectin during early differentiation. We show that this is accompanied by a partial blockage of the transcriptional induction of proline-rich tyrosine kinase 2, a gene coding for a focal adhesion kinase active in monocytes, and of tissue transglutaminase, a gene coding for a fibronectin coreceptor in monocytes. This is the first report that demonstrates the involvement of a Hox gene in the regulation of adhesion and migration of hematopoietic cells and that links it to the deregulation of genes involved in cell-ECM interactions and downstream signaling pathways.


Assuntos
Diferenciação Celular/genética , Movimento Celular/genética , Regulação para Baixo/genética , Fibronectinas/metabolismo , Proteínas de Homeodomínio/metabolismo , Monócitos/metabolismo , Proteínas de Neoplasias/metabolismo , Adesão Celular/genética , Linhagem Celular Tumoral , Técnicas de Cocultura , Fibronectinas/farmacologia , Quinase 2 de Adesão Focal , Regulação da Expressão Gênica no Desenvolvimento/genética , Células HL-60 , Proteínas de Homeodomínio/genética , Humanos , Integrina alfa5beta1/genética , Integrina alfa5beta1/metabolismo , Integrinas/metabolismo , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Monócitos/citologia , Monócitos/efeitos dos fármacos , Proteínas de Neoplasias/genética , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/metabolismo , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Células Estromais/metabolismo , Transcrição Gênica/genética , Transglutaminases/genética , Transglutaminases/metabolismo
9.
J Immunol ; 172(1): 585-92, 2004 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-14688370

RESUMO

In this study, we address the question of the cross-talk between two chemokines that are cosecreted during inflammation, namely monocyte chemoattractant protein-1 (MCP-1) and soluble fractalkine (s-FKN), toward monocyte migration. We found that s-FKN fails to induce MonoMac6 cell migration per se. Interestingly, this chemokine antagonizes transendothelial migration and chemotaxis of MonoMac6 cells and freshly isolated human monocytes induced by MCP-1, indicating a direct effect of s-FKN on monocytic cells. In this study, we found that stress-activated protein kinase (SAPK)1/c-Jun N-terminal kinase 1 and SAPK2/p38 are involved in the control of MCP-1-induced MonoMac6 cell migration. We demonstrated that s-FKN abrogates the MCP-1-induced SAPK2/p38 activation as well as the upstream Pyk2 activity. Furthermore, we observed that s-FKN also inhibits the activity of a major matrix metalloproteinase (MMP), namely MMP-2. Taken collectively, our results indicate that the s-FKN antagonizes the chemoattractant effect of MCP-1 on monocytes, likely by inhibiting crucial signaling pathways, like SAPK2/p38 and MMP-2 activities.


Assuntos
Inibição de Migração Celular , Quimiocina CCL2/fisiologia , Quimiocinas CX3C/fisiologia , Quimiotaxia de Leucócito/imunologia , Inibidores de Metaloproteinases de Matriz , Proteínas de Membrana/fisiologia , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Monócitos/enzimologia , Linhagem Celular , Linhagem Celular Tumoral , Separação Celular , Quimiocina CCL2/antagonistas & inibidores , Quimiocina CX3CL1 , Endotélio Vascular/citologia , Endotélio Vascular/imunologia , Ativação Enzimática/imunologia , Indução Enzimática/imunologia , Inibidores Enzimáticos/farmacologia , Quinase 2 de Adesão Focal , Humanos , Metaloproteinase 2 da Matriz/biossíntese , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 2 da Matriz/fisiologia , Proteínas Quinases Ativadas por Mitógeno/biossíntese , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Monócitos/citologia , Monócitos/imunologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/biossíntese , Proteínas Tirosina Quinases/metabolismo , Solubilidade , Proteínas Quinases p38 Ativadas por Mitógeno
10.
J Bone Miner Res ; 18(10): 1863-71, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14584897

RESUMO

UNLABELLED: Molecular events of mechanotransduction in osteoblasts are poorly defined. We show that the mechanosensitive BK channels open and recruit the focal adhesion kinase FAK in osteoblasts on hypotonic shock. This could convert mechanical signals in biochemical events, leading to osteoblast activation. INTRODUCTION: Mechanical strains applied to the skeleton influence bone remodeling and architecture mainly through the osteoblast lineage. The molecular mechanisms involved in osteoblastic mechanotransduction include opening of mechanosensitive cation channels and the activation of protein tyrosine kinases, notably FAK, but their interplay remains poorly characterized. The large conductance K+ channel (BK) seems likely as a bone mechanoreceptor candidate because of its high expression in osteoblasts and its ability to open in response to membrane stretch or hypotonic shock. Propagation of the signals issued from the mechanosensitivity of BK channels inside the cell likely implies complex interactions with molecular partners involved in mechanotransduction, notably FAK. METHODS: Interaction of FAK with the C terminus of the hSlo alpha-subunit of BK was investigated using the yeast two-hybrid system as well as immunofluorescence microscopy and coimmunoprecipitation experiments with a rabbit anti-hslo antibody on MG63 and CAL72 human osteosarcoma cell lines and on normal human osteoblasts. Mapping of the FAK region interacting with hSlo was approached by testing the ability of hSlo to recruit mutated ot truncated FAK proteins. RESULTS: To the best of our knowledge, we provide the first evidence of the physical association of FAK with the intracellular part of hslo. We show that FAK/hSlo interaction likely takes place through the Pro-1-rich domain situated in the C-terminal region of the kinase. FAK/hSlo association occurs constitutively at a low, but appreciable, level in human osteosarcoma cells and normal human osteoblasts that express endogenous FAK and hSlo. In addition, we found that application of an hypo-osmotic shock to these cells induced a sustained activation of BK channels associated to a marked increase in the recruitment of FAK on hSlo. CONCLUSIONS: Based on these data, we propose that BK channels might play a triggering role in the signaling cascade induced by mechanical strains in osteoblasts.


Assuntos
Cálcio/metabolismo , Osteoblastos/metabolismo , Canais de Potássio Cálcio-Ativados/metabolismo , Proteínas Tirosina Quinases/metabolismo , Animais , Células COS , Linhagem Celular , Linhagem da Célula , Eletrofisiologia , Quinase 1 de Adesão Focal , Proteína-Tirosina Quinases de Adesão Focal , Humanos , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta , Canais de Potássio Ativados por Cálcio de Condutância Alta , Microscopia Confocal , Microscopia de Fluorescência , Modelos Biológicos , Osteoblastos/patologia , Plasmídeos/metabolismo , Canais de Potássio/química , Testes de Precipitina , Ligação Proteica , Estrutura Terciária de Proteína , Transdução de Sinais , Técnicas do Sistema de Duplo-Híbrido
11.
FASEB J ; 17(12): 1751-3, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12958198

RESUMO

Bone resorption is regulated by the immune system, where receptor activator of nuclear factor (NF)kappaB ligand (RANKL), a new member of the tumor-necrosis factor family, may contribute to pathological conditions. Due to the role of RANKL in the maturation of monocyte-derived osteoclasts, we hypothesized that RANKL could exert chemotactic properties toward monocytic cells. Our results demonstrate that RANKL induces the migration of MonoMac-6 monocytic cells as well as human freshly isolated total peripheral blood mononuclear cells (PBMC) and CD14+ purified PBMC. RANKL induces the migration of MonoMac-6 cells in a dose-dependent manner and with an efficacy similar to MCP-1. After an 8-h incubation, the soluble form of RANKL (sRANKL) started to exhibit a chemoattractive effect on MonoMac-6 cells, with an increased effect observed up to 24 h. RANKL elicits an additive chemotactic effect to MCP-1. Furthermore, addition of the RANKL decoy receptor osteoprotegerin in the lower well or RANKL in the upper well abrogates the RANKL-induced migration of MonoMac-6 cells, hallmarking a true specific activity. RNase protection assay experiments indicate that exposure of MonoMac-6 cells to RANKL had no significant effect on the expression of a variety of chemokines, known to attract monocytes. This study provides evidence that RANKL behaves as a chemotactic factor for monocytic cells, emphazing the cross-talk between bone and immune systems.


Assuntos
Proteínas de Transporte/farmacologia , Fatores Quimiotáticos/farmacologia , Glicoproteínas de Membrana/farmacologia , Monócitos/imunologia , Linhagem Celular , Quimiocina CCL2/farmacologia , Quimiotaxia/efeitos dos fármacos , Sinergismo Farmacológico , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Modelos Imunológicos , Monócitos/efeitos dos fármacos , Ligante RANK , Receptor Ativador de Fator Nuclear kappa-B
12.
Infect Immun ; 71(4): 1774-83, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12654791

RESUMO

Ulcerative colitis and Crohn's disease are inflammatory bowel diseases thought to involve strains of Escherichia coli. We report here that two wild-type Afa/Dr diffusely adhering E. coli (DAEC) strains, C1845 and IH11128, which harbor the fimbrial F1845 adhesin and the Dr hemagglutinin, respectively, and the E. coli laboratory strain HB101, transformed with the pSSS1 plasmid to produce Afa/Dr F1845 adhesin, all induced interleukin-8 (IL-8) production and transepithelial migration of polymorphonuclear leukocytes (PMNL) in polarized monolayers of the human intestinal cell line T84 grown on semipermeable filters. We observed that after PMNL migration, expression of decay-accelerating factor (DAF, or CD55), the brush border-associated receptor for Afa/Dr adhesins, was strongly enhanced, increasing the adhesion of Afa/Dr DAEC bacteria. When examining the mechanism by which DAF expression was enhanced, we observed that the PMNL transepithelial migration induced epithelial synthesis of tumor necrosis factor alpha and IL-1beta, which in turn promoted the upregulation of DAF.


Assuntos
Adesinas de Escherichia coli/metabolismo , Aderência Bacteriana , Antígenos CD55/metabolismo , Escherichia coli/patogenicidade , Infiltração de Neutrófilos , Regulação para Cima , Adesinas de Escherichia coli/genética , Adesinas de Escherichia coli/fisiologia , Polaridade Celular , Citocinas/metabolismo , Escherichia coli/genética , Escherichia coli/imunologia , Escherichia coli/fisiologia , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Células HeLa , Hemaglutininas/genética , Hemaglutininas/metabolismo , Humanos , Microscopia Eletrônica , Neutrófilos/imunologia , Células Tumorais Cultivadas
13.
Eur J Haematol ; 70(1): 43-52, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12631258

RESUMO

Permanent osteoblastic cell lines are potential tools to study the interactions between osteoblastic and hematopoietic cells in the bone marrow cavity. In a recent work we have shown that the osteosarcoma cell line CAL72 may be more closely related to normal osteoblasts than the osteosarcoma cells previously described. In the present work we continued the characterisation of the CAL72 cell line with regard to its effects on various hematopoietic cells, in coculture experiments. We show here that CAL72 cells, in contrast to MG-63 or SaOS-2 osteosarcoma cell lines, do not inhibit hematopoietic colony formation and sustain the limited expansion of hematopoietic progenitors in a similar way to that described for normal osteoblasts. We also demonstrate that CAL72 cells induce the monocytic differentiation of the promyelocytic HL-60 cell line like MG-63 and SaOS-2, but support a better maturation and a longer survival of the differentiated cells than the two other osteosarcoma cell lines. In order to better understand the differential effects observed between CAL72 and MG-63 or SaOS-2, we analysed the cytokine and chemokine mRNA expression of these cells using the RNase protection quantitative assay. We show here that the expression profile of CAL72 is clearly different from that of MG-63 or SaOS-2 and may explain, at least in part, its specific effects on hematopoietic cells. Taken together these experiments confirm that CAL72 has particular properties and is an interesting tool to study the role of osteoblastic cells in hematopoietic cell growth and differentiation.


Assuntos
Comunicação Celular , Células-Tronco Hematopoéticas/citologia , Osteoblastos/fisiologia , Células Tumorais Cultivadas/citologia , Células da Medula Óssea/citologia , Células da Medula Óssea/fisiologia , Neoplasias da Medula Óssea/patologia , Diferenciação Celular , Divisão Celular , Técnicas de Cocultura , Sangue Fetal/citologia , Células HL-60 , Hematopoese , Humanos , Osteossarcoma/patologia
14.
Infect Immun ; 71(3): 1068-74, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12595416

RESUMO

Afa/Dr diffusely adhering Escherichia coli (Afa/Dr DAEC) strains cause symptomatic urinary tract and intestinal infections. The proinflammatory effects of Afa/Dr DAEC strains in vitro have been not investigated to date. In the present study, we used confluent polarized monolayers of intestinal cell line T84 to evaluate the consequences of epithelial infection by Afa/Dr DAEC strains in terms of proinflammatory response. Polymorphonuclear leukocyte (PMNL) migration across the epithelial barrier was induced after incubation of the T84 monolayers with the wild-type Afa/Dr DAEC strain C1845 harboring the fimbrial F1845 adhesin and strain IH11128 harboring the Dr hemagglutinin, and the E. coli laboratory strain HB101 was transformed with the pSSS1 plasmid, producing Afa/Dr F1845 adhesin. PMNL migrations were correlated with a basolateral secretion of interleukin-8 by T84 cells and were abolished after incubation of epithelial cells with an anti-decay accelerating factor (DAF) antibody that recognized the short consensus repeat 3 domain of DAF (monoclonal antibody 1H4). Moreover, Afa/Dr DAEC strains induced tyrosine phosphorylation of several T84 proteins and activated the mitogen-activated protein kinases (ERK1/2 mitogen-activated protein, P38, and Jun-C kinases). These data demonstrated for the first time that, in vitro, Afa/Dr DAEC strains exert a proinflammatory signal in intestinal epithelial cells.


Assuntos
Adesinas de Escherichia coli/fisiologia , Aderência Bacteriana , Escherichia coli/fisiologia , Interleucina-8/biossíntese , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neutrófilos/fisiologia , Movimento Celular , Polaridade Celular , Células Cultivadas , Ativação Enzimática , Humanos , Mucosa Intestinal/microbiologia , Fosforilação , Transdução de Sinais , Tirosina/metabolismo
15.
Infect Immun ; 71(3): 1161-9, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12595428

RESUMO

Some strains of Escherichia coli related to acute cystitis or colitis produce a toxin named cytotoxic necrotizing factor 1 (CNF-1). CNF-1 mediates its effects on epithelial cells or phagocytes via the permanent activation of small GTP-binding proteins, caused by the toxin-induced deamidation of Glu(63) of p21 Rho. The behavior of peripheral blood T lymphocytes during the acute phase of bacterial colitis has been poorly investigated. Our study was conducted to test whether (i) peripheral blood T lymphocytes can be activated by CNF-1 and (ii) CNF-1-activated T lymphocytes are cytotoxic against intestinal epithelial cells. Activation of T lymphocytes by CNF-1 was assessed by electrophoresis, flow cytometry, confocal microscopy, and electron microscopy studies. Assays for migration and adherence of CNF-1-treated T lymphocytes were performed in Transwell chambers with T84 intestinal epithelial cells grown on polycarbonate semipermeable filters. CNF-1 induced a decrease in the electrophoretic mobility of the GTP-binding protein Rho in treated T lymphocytes. CNF-1 provoked an increase in the content of actin stress fibers and pseudopodia in T lymphocytes. Several adherence molecules were clustered into cytoplasmic projections in CNF-1-treated T lymphocytes and adherence of such lymphocytes on the basolateral pole of T84 was increased, resulting in cytotoxicity toward epithelial cells. Such enhanced adherence in response to CNF-1 was dependent on p42-44(MAP) kinase activation of T lymphocytes. Taken together, these results suggest that CNF-1, by acting on T lymphocytes, may increase in an important fashion the virulence of certain strains of E. coli against the intestinal epithelia.


Assuntos
Toxinas Bacterianas/toxicidade , Citotoxinas/toxicidade , Proteínas de Escherichia coli , Mucosa Intestinal/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Proteínas rho de Ligação ao GTP/metabolismo , Antígeno CD11a/metabolismo , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Quimiocina CXCL12 , Quimiocinas CXC/farmacologia , Ativação Enzimática , Humanos , Imunofenotipagem , Integrina beta1/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Linfócitos T/enzimologia , Linfócitos T/fisiologia , Fator de Crescimento Transformador beta/biossíntese , Fator de Necrose Tumoral alfa/biossíntese
16.
J Bone Miner Res ; 17(5): 869-78, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12009018

RESUMO

Prostaglandins (PGs) are important mediators of bone response to growth factors, hormones, inflammation, or mechanical strains. In this study, we show that in MG63 osteosarcoma cells, prostaglandin E2 (PGE2) produces the opening of a large conductance Ca2+-dependent K+ channel (BK). This PGE2-mediated channel opening induces the recruitment of various tyrosine-phosphorylated proteins on the hSlo alpha-subunit of BK. Because the C-terminal domain of hSlo encompasses an immunoreceptor tyrosine-based activation motif (ITAM), we show that the Syk nonreceptor tyrosine kinase, reported yet to be expressed mainly in hematopoietic cells, is expressed also in osteoblastic cells, and recruited on this ITAM after a PGE2-induced docking/activation process. We show that Syk/hSlo association is dependent of an upstream Src-related tyrosine kinase activity, in accord with the classical two-step model described for immune receptors. Finally, we provide evidence that this Syk/hSlo interaction does not affect the electrical features of BK channels in osteosarcoma cells. With these data, we would like to suggest the new notion that besides its conductance function, hSlo channel can behave in bone cells, as a true transduction protein intervening in the bone remodeling induced by PGE2.


Assuntos
Dinoprostona/farmacologia , Precursores Enzimáticos/metabolismo , Canais de Potássio Cálcio-Ativados/metabolismo , Proteínas Tirosina Quinases/metabolismo , Sequência de Aminoácidos , Animais , Remodelação Óssea/efeitos dos fármacos , Remodelação Óssea/fisiologia , Células COS , Ativação Enzimática , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta , Canais de Potássio Ativados por Cálcio de Condutância Alta , Dados de Sequência Molecular , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteossarcoma/metabolismo , Técnicas de Patch-Clamp , Canais de Potássio Cálcio-Ativados/química , Canais de Potássio Cálcio-Ativados/genética , Transdução de Sinais , Quinase Syk , Células Tumorais Cultivadas , Quinases da Família src/metabolismo
17.
Hepatology ; 35(5): 1144-52, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11981764

RESUMO

The cytosine deaminase (CD) gene converts the nontoxic prodrug, 5-fluorocytosine (5-FC), into 5-fluorouracil (5-FU). We previously showed that injection of CD-bearing cancer cells followed by 5-FC treatment can act as an autologous tumor vaccine in a syngenic liver metastasis model in rats. In the present work, we analyzed the antitumor efficiency of a direct intratumoral injection of a CD-expressing plasmid. In rats bearing microscopic or macroscopic metastases in right and left liver lobes, an injection of a CD-expressing plasmid was performed in the left lobe tumor, followed by 5-FC treatment of the animals. A significant regression of the DNA-injected tumor was observed in 5-FC-treated rats, both in microscopic (P =.007) or advanced (P <.0001) tumor models. Moreover, this treatment also induced a potent distant bystander effect on untreated controlateral liver tumors and extrahepatic metastases, resulting in an increased survival compared with control animals in both tumor models (P <.05). In conclusion, these data suggest that direct intratumoral injection of a CD-expressing plasmid, associated to 5-FC administration, can constitute a powerful and innocuous alternative treatment for unresectable liver metastases from colon carcinoma.


Assuntos
Terapia Genética , Neoplasias Hepáticas Experimentais/secundário , Neoplasias Hepáticas Experimentais/terapia , Nucleosídeo Desaminases/genética , Plasmídeos/farmacologia , Animais , Antimetabólitos/farmacocinética , Neoplasias do Colo , Citosina Desaminase , Modelos Animais de Doenças , Flucitosina/farmacocinética , Fluoruracila/metabolismo , Técnicas de Transferência de Genes , Hepatectomia , Células Matadoras Naturais/imunologia , Neoplasias Hepáticas Experimentais/mortalidade , Masculino , Transplante de Neoplasias , Ratos , Ratos Endogâmicos , Taxa de Sobrevida , Células Tumorais Cultivadas/transplante
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